Erik@LCD

Looking for some help here, this is one we haven't seen before.
Have an 04.5 manual truck that has a cyclic rattle at idle. Every 7 seconds or so, it has what sounds like an injector or lifter rattle. Hooked up to the scan tool, this sound corresponds to a change from 5500psi (ish..normal idle pressure) to a spike of 10-13kpsi. I suspect the noise is the injectors rattling or a return valve rattling. The cause is the question.

I am leaning to the FCA as the cause. Any thoughts or similar experiences?

Thanks!

2007 5.9

Erik,

I have the same noise with my ride. It is more predominant in the morning, but I can hear it all the time until I reach approx. 7psi then it goes away....but it comes and goes bout every 5-10 sec, almost like a vibration rattle????

Erik@LCD

hmm, no kidding,Les. Did you have it before the sticks?

2007 5.9

no I did not have it before the stix, but I also
did not have before running TNT!!

tim barney

my 2004.5 started to make a rattling noise that seamed to come from the from the number one fuel line. when the engine makes the tapping noise it also can be felt. it did not give any codes at first but a day later p0251 then after unplugging wires at back of cp3 it spit out a p0088. then driving home the engine light came on. still runs fine. i parked it until i get it figued out. i am thinking maybe bad number one injector , one mechanic said possibly a cracked injector. i pull a lot without any mods other than an s&b air intake.

Erik@LCD

FYI, on this customer's truck, replacing the FCA solved the problem. It audibly changed the idle and the low-end smoothness of the truck improved dramatically.

2007 5.9

Good to know there Erik....maybe need to go get a FCA just for the sake of it....

dwo3rd

ok , what is FCA?

2007 5.9

Fuel Control Actuator...controls the ramp angle of pressure that the CP3 puts out to the Common Rail...the more it moves, the faster the pressure ramp is!

cgmorgan06

This sounds very similar to a rattle that my truck has been making lately. It likes to do it in the morning before it gets warmed up and at no to small amounts of boost. However I dont have a rail pressure guage so I cant tell what the rp is doing? But after the truck gets warmed up, then noise fades away. Eric or 2007 5.9, does this sound like similar symptoms to the issues related with your truck? Did just an FCA fix the problem completely?

cgmorgan06

just a bump........

2007 5.9

Your sound is very similar to mine...have not tried the FCA yet. My RP stays very constant while sitting still, and also when driving it does not fluctuate very much....I will swap FCA soon. I will post update when I get to it!

cgmorgan06

Do you think that since it happened after you installed your injectors that they had anything to do with it?

2007 5.9

I have no idea!!!

Right now it does not bother me enough to change the FCA, but once it does I will swap and see if it goes away...

N.Johnson

I,ve got to give you my opinion on this one. You lucky buggers with a rail pressure gauge (next mod) can be sure if your seeing a 2000 psi difference at idle your FCA is going. That is if your not stacked with multiple fueling chips/downloaders. For the others with a rough vibrating cold start idle you have got carbon build up on your tips, ruining the spray pattern causing a screwed up idle. I know it has happened to me many times. Nature of the cummins medium duty industrial engine in a pick-up. I'm still on the oem fca due to the fass filtration. I don't care what system you got on your rig but get the fuel supply filtered down to 3 microns or better. Carbon will still build up as most of us don't work these motors as designed. By the way hot rodding quick light to light won't clean the tips of varnish&carbon build-up. Only thing I have found is towing/hauling loads with sustained egt's over 900F..........